Over the past 12 years, audio archivists at the The Macaulay Library archive at the Cornell Lab of Ornithology have digitized 7,513 hours of analog recordings of natural sounds. The collection houses the largest and oldest scientific archive of biodiversity audio and video recordings, and the entire collection is now accessible online.

Once heard, the “coda” song of the male walrus is one of those unforgettable sounds in the world. It is comprised of two basic types of elements, series of evenly-delivered taps followed by an extraordinary bell or gong-like sound. The ringing quality of this latter element is astonishing, especially in an aquatic environment, and that such a sound is produced by a walrus seems all the more improbable (but true). The function is not fully understood, but may convey dominance status to potential mates and rivals.

The Macaulay Library’s goal is to build the most comprehensive collection of natural sounds and to preserve such recordings. There is even an “Audio Most Wanted” list to help build the archive.